Can you please help with the following question with a picture demo??

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1 Answer
Feb 19, 2018

Rate of change of elevation is #9/25# radians per second

Explanation:

The situation described in question is indicated in following picture, where after moving drone vertically up #x# feet, the angle #theta# is given by #theta=tan^(-1)(x/30)#

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and as it is moving at #2(ft)/s# after #t# seconds, #theta# is given by

#theta=tan^(-1)((2t)/30)=tan^(-1)(t/15)#

and rate of change of elevation is

#(d theta(t))/(dt)=1/(1+(t/15)^2)=225/(225+t^2)#

and as it reaches #40# feet after #40/2=20# seconds, rate of change of elevation is given by

#(d theta(20))/(dt)=225/(225+400)=225/625=9/25# radians per second